Prosecutors have sought phone records from reporters before, but the seizure of records from such a wide array of AP offices, including general AP switchboards numbers and an office-wide shared fax line, is unusual.

In the letter notifying the AP received Friday, the Justice Department offered no explanation for the seizure, according to Pruitt’s letter and attorneys for the AP. The records were presumably obtained from phone companies earlier this year although the government letter did not explain that. None of the information provided by the government to the AP suggested the actual phone conversations were monitored.